/*************************************************************************************

#

#       scrolls.c

#

#       This segment handles the scroll bars.

#

#       Author(s):  Michael Marinkovich & Guillermo Ortiz

#                   marink@apple.com

#

#       Modification History: 

#

#           4/3/96      MWM     Initial coding                   

#

#       Copyright © 1992-96 Apple Computer, Inc., All Rights Reserved

#

#

#       You may incorporate this sample code into your applications without

#       restriction, though the sample code has been provided "AS IS" and the

#       responsibility for its operation is 100% yours.  However, what you are

#       not permitted to do is to redistribute the source as "DSC Sample Code"

#       after having made changes. If you're going to re-distribute the source,

#       we require that you make it clear in the source that the code was

#       descended from Apple Sample Code, but that you've made changes.

#

*************************************************************************************/

#include <Events.h>

#include <ToolUtils.h>

#include <Gestalt.h>

#include <OSUtils.h>

#include "App.h"

#include "Proto.h"

//----------------------------------------------------------------------

//

//  Globals - 

//

//----------------------------------------------------------------------

extern Boolean      gInBackground;

//----------------------------------------------------------------------

//

//  InstallScrollBars -

//               

//

//----------------------------------------------------------------------

void InstallScrollBars(WindowRef window, DocHnd doc)

{

    Rect        bounds;

    // calc horiz scroll bar

    bounds = window->portRect;

    bounds.right++;

    bounds.left = bounds.right - (kScrollWidth + 1);

    bounds.top--;

    bounds.bottom -= (kScrollWidth - 1);

    (**doc).hScroll = NewControl(window, &bounds, nil, true,

                                  0, 0, 0, scrollBarProc, nil);

    // calc vert scroll bar

    bounds = window->portRect;

    bounds.left--;

    bounds.right -= (kScrollWidth - 1);

    bounds.top = bounds.bottom - kScrollWidth;

    bounds.bottom++;

    (**doc).vScroll = NewControl(window, &bounds, nil, true,

                                  0, 0, 0, scrollBarProc, nil);

}

//----------------------------------------------------------------------

//

//  AdjustScrollValues -

//               

//

//----------------------------------------------------------------------

void AdjustScrollValues(WindowRef window)

{

    Rect                    contRect;

    Rect                    picFrame;

    ControlHandle           hCntrl;

    ControlHandle           vCntrl;

    short                   oldValue;

    short                   lines;

    short                   max;

    DocHnd                  doc;

    doc = (DocHnd)GetWRefCon(window);

    if (doc != nil) {

        hCntrl = (**doc).hScroll;

        vCntrl = (**doc).vScroll;

        GetContRect(window,&contRect);

        if ((**doc).pict != nil || (**doc).world != nil)

            picFrame = (**doc).world->portRect;

        else

            SetRect(&picFrame, 0, 0, 0, 0);

        oldValue = GetCtlValue(vCntrl);

        lines = picFrame.bottom - picFrame.top;

        max = lines - contRect.bottom ;

        if ( max < 0 ) max = 0;

        SetCtlMax(vCntrl, max);

        if(oldValue + contRect.bottom > lines)

            SetCtlValue(vCntrl, max);

        oldValue = GetCtlValue(hCntrl);

        lines = picFrame.right - picFrame.left;

        max = lines - contRect.right;

        if ( max < 0 ) max = 0;

        SetCtlMax(hCntrl, max);

        if(oldValue + contRect.right > lines)

            SetCtlValue(hCntrl, max);

    }       

}

//----------------------------------------------------------------------

//

//  AdjustScrollbars -

//               

//

//----------------------------------------------------------------------

void AdjustScrollbars(WindowRef window, Boolean resize)

{

    ControlRef      hCtl;

    ControlRef      vCtl;

    Rect            r;

    DocHnd          doc;

    doc = (DocHnd)GetWRefCon(window);

    if (doc != nil && resize) {

        hCtl = (**doc).hScroll;

        vCtl = (**doc).vScroll;

        GetContRect(window, &r);

        // resize horizontal

        MoveControl(hCtl, -1, r.bottom);

        SizeControl(hCtl, (r.right - r.left) + 2, kScrollWidth + 1);

        // resize vertical

        MoveControl(vCtl, r.right, -1);

        SizeControl(vCtl, kScrollWidth + 1, r.bottom + 2);

    }

    // adjust scrollbar values to match

    AdjustScrollValues(window);

}

//----------------------------------------------------------------------

//

//  ScrollActionProc -

//               

//

//----------------------------------------------------------------------

pascal void ScrollActionProc(ControlRef control, short part)

{

    WindowRef       window;

    short           amount;

    short           value;

    short           max;

    short           hAmount;

    short           vAmount;

    DocHnd          doc;

    window = (**control).contrlOwner;

    doc = (DocHnd)GetWRefCon(window);

    if (doc != nil) {

        if ( part != 0 ) {              

            window = (*control)->contrlOwner;

            hAmount = vAmount = 0;

            value = GetCtlValue(control);   

            max = GetCtlMax(control);       

            switch ( part ) {

                case inUpButton:

                case inDownButton:      // one line

                        amount = 8;

                        break;

                case inPageUp:          // one page

                case inPageDown:

                        amount = 64;

                        break;

            }

            if ( (part == inDownButton) || (part == inPageDown) )

                amount = -amount;       // reverse direction for a downer

            amount = value - amount;

            if ( amount < 0 )

                amount = 0;

            else if ( amount > max )

                amount = max; 

            SetCtlValue(control, amount);

            amount = value - amount;        // calculate the real change

            if ( amount != 0 ) {

                if (control == (**doc).hScroll)

                    hAmount = amount;

                else

                    vAmount = amount ;

                MyScrollPicture(window,hAmount, vAmount);

            }

        }   

    }   

}

//----------------------------------------------------------------------

//

//  MyScrollPicture -

//               

//

//----------------------------------------------------------------------

void MyScrollPicture(WindowRef window, short hs, short vs)

{

    RgnHandle       updateRgn;

    GWorldPtr       oldWorld;

    GWorldPtr       theWorld;

    GDHandle        oldGD;

    PixMapHandle    thePix;

    Rect            contRect;

    Rect            pictRect;

    DocHnd          doc;

    doc = (DocHnd)GetWRefCon(window);

    if (doc != nil) {

        GetGWorld(&oldWorld, &oldGD);

        SetPort(window);

        GetContRect(window, &contRect);

        ScrollRect(&contRect, hs, vs, updateRgn = NewRgn());

        theWorld = (**doc).world;

        pictRect = theWorld->portRect;

        thePix = GetGWorldPixMap(theWorld);

        if (LockPixels(thePix)) {

            SetGWorld((CGrafPtr)window, nil);

            OffsetRect(&pictRect, -GetCtlValue((**doc).hScroll), 

                      -GetCtlValue((**doc).vScroll));

            CopyBits((BitMap *) *thePix, &window->portBits,

                    &theWorld->portRect, &pictRect, srcCopy,updateRgn);

            UnlockPixels(thePix);

            SetGWorld(oldWorld, oldGD);

        }           

        ClipRect(&window->portRect);

        DisposeRgn(updateRgn);

    }

}   

//----------------------------------------------------------------------

//

//  GetContRect -

//               

//

//----------------------------------------------------------------------

void GetContRect(WindowRef window,Rect *contRect)

{

    *contRect = window->portRect;   // get the content rect for our window

    contRect->right -= 15;          // subtract the scroll bars from the rect

    contRect->bottom -= 15;

}